Casein waterproof glue or cement



Patented May 19, 1925.

ANDREW A. DUNHAM, OF BAINBRIDGE, NEW

FACTURING COMPANY, OF NEW YORK, N.

YORK, ASSIGNOR To oAsEIN ANU' Y., A ooaroanrron or VERMONT.

CASEIN WATERPROOF GLUE OR CEMENT.

Ho Drawing.

To all whom it may concern:

Be it known that 1, ANDREW A. DUNHAM, a citizen of the United States, and a resident of Bainbridge, Chenango County, New York, have invented certain new and'useful Improvements in Casein Waterproof Glues or Cements, of which the following is a specification.

This invention has for its object, improvements in casein'water-proof glues or cements and in the process of manufacturing them.

In the production of casein Water-proof glues or cements the manufacturer aims to give certain characteristics to such glues or cements such as: (a) setting or jelling while the glues or cements are yet in solution; (6) setting or jelling within a predetermined period after the preparation of the glue or cement-a period that shall not be too short nor too long; (0) being as viscous as possible, yet possessing a free, even flow.

The control of the life of the glue or cement solution i. e., of the length of time before it sets or jells, is of very great importance, and I have found that it is dilficult to effect this and still preserve the strength of the glue or cement. One method of controlling the life of the glue or cement is to increase the proportion of the casein solvents to thecasein in the glue or cement. This expedient has the effect of weakening the glue or cement. Unless the very greatest care is used in blending the available commercial caseins the glue or cement prepared therefrom will not be quite satisfactory, it being well known that commercial caseins are lacking in uniformity. Some casein glues or cements, when dissolved in a given quantity of water, produce a solution that is so heavy that it will not flow freely, while others, prepared with the same quantity of water, yield a solution that is so thin that it cannot be used with any de gree of satisfaction, not only because the machinery ordinarily employed in gluing operations will not properly apply the ad- Application filed March 26, 1923. Serial No. 627,738.

hesive, but because the solution penetrates proof glues or cements without weakening in any degree the strength thereof; secondly, to stabilize the viscosity of their solutions, so that they may flow freely, thus permitting them to be handled to advantage by machines which are used for the purpose of applying adhesives, and yet possess a viscosity sufliciently heavy to prevent the solution from penetrating too deeply into the fibres of the wood or other material to be glued; and, thirdly, to render available for glue making purposes grades of casein which otherwise would be unsuitable therefor.

I have discoveredthat these characteris tics may be communicated to casein waterproof glues o'r cements by incorporating therewith, at the time of manufacture, a small percentage of animal glue in a form or condition in which it will be readily soluble in cold water. glue, or an analogous gelatinous substance, or a mixture thereof, maybe used.

There are various methods by which the animal glue not already in a condition to be readily soluble in cold water may be put into a form or condition in which it will be readily soluble in cold water.

For instance the animal glue may be dissolved by heating the glue in Water until it has been brought to a fairly thin solution as, e. g., by the employment of 4 lbs. of Water to 1 lb. of glue. Thissolution is then dried by bringing it in the form of a thin film into contact with a moving surface or support heated to a temperature that will expel the nioisture from the glue. In practice I prefer to dry the thin solution of animal glue, above referred to, on a rotating steam heated cylinder heated to a tempera- Either bone glue, hide ture of 212 degrees F. or above, so arranged that the cylinder takes up a thin film of solution allowing it to dry in one revolutionthe cylinder being provided with a scraper or knife to remove the film after it has dried. Apparatus of this description and. used for this purpose is well known in the art. I have found that very satisfactory results are obtained by treating the glue in this manner, the glue being thus obtained in the form of porous fluffy flakes.

Another method for getting animal glue into a form in which it will dissolve readily in cold water is to make up a solutionof the animal glue and spray it as a fine mist into a chamber in which said mist is exposed to currents of heated air which will effect an evaporation of the water in this mist and permit the animal glue to deposit, in a highly divided dry form, within the said chamber.

Another method for getting the animal glue into a form in which it will dissolve readily in cold water is by attrition. The animal glue may be ground by any wellknown method until it has been brought to the condition of a powder, in which form a large surface of glue is presented in proportion to the solvent employed. The difficulty of carrying out this method is however such that under ordinary circum stances it is not as satisfactory as the methods above described.

The methods hereinabove described are well known-to the art of drying glue.

The method which I prefer is, however, the one hereinafter described in which the glue is simultaneously dried and mixed with the casein.

Casein water-proof glue or cement is usually composed of a body of finely ground casein, approximately 7 0 parts, calcium hydroxide approximately 20 parts, other casein solvents and chemicals: approximately 10 parts. I find that by adding to such glue of the above general formula an amount of cold-water-soluble .animal glue of a weight approximately 10% of the dry weight of such casein glue or cement, I am able to control its time of jelling and to give it a heavy body without impairing its free flowing characteristics, the time of jelling being determined by the proportion of animal glue added. The addition of much more or much less than such 10% will cause the casein glue or cement to set too quickly for practical purposes. For all practical pur poses the limits may be regarded as from 5% to The time of setting is dependent also upon the character of the animal glue used so that tests with different proportions ofthe materials to be used will be necessary to determine what proportions are to be used in any particular case in order to cause the casein glue or cement to jell or the casein.

set at the desired time. The addition of animal glue increases the strength of casein water-proof glues and cements.

I do not wish to limit myself to any partieular formula for casein water-proof glues and cements, nor to any definite percentage of cold water soluble animal glue to be added to such casein water-proof lues or cements, especially because glue ormulas other than that hereinabove given may be used, and because both casein and animal glue vary in composition and characteristics; also because the completed glue may be used for widely different pur oses and may, therefore, have to possess wldely differentcharacteristics.

My preferred method of preparin the mixture of animal glue and casein g ue is one which at the same time renders the animal glue readily soluble in cold water.

I place the casein which is to be used in making up the casein water-proof glue or cement in a rapidly rotating agitator. To

this casein, which is preferably unground, I add while it is being rapidly agitated, a solution of animal glue. This solution thoroughly coats each particle of casein with a very thin coat of animal glue. The casein and animal glue mixture are removed from the mixer, dried and ground to' a fine mesh and is then ready for the manufacture of casein. water-proof glue or cement by the addition of suitable chemicals.

This specific manner of mixing casein and animal glue is the same as that described and claimed in my United States Letters Patent No. 739,657, September 22, 1903, relating to sizing and process of producing same and therefore I do not here make any claim thereto.

It is well known to all those skilled in the art that it is necessary to use, for the manufacture of so-calledv waterproof casein glues, one or more of the alkaline earth oxids or hydroxids in considerable excess above the amount of such material necessary to dis solve the casein. lVhile the oxids or hydroxids of strontium barium and magne" sium may be used, the oxid or hydroxid of calcium is almost universally employed because it is least expensive and gives the best results. lVhen in my claims I speak of waterproof casein glue, I refer to a glue made with the use of a suitable proportion of the oxid or hydroxid of an alkaline earth greater than that needed merely to dissolve As, however, is Well known, another solvent, or other solvents, may be substituted for somuch as, or less than, the amount of the alkaline earth oxid or hydroxid as is necessary merely to dissolve the casein (enough of the oxidor hydroxid being used to secure the desired waterproof characteristics of the glue), I desire it to be understood that such use of such other sol- -oxid or hydroxid. When I claims of hydroxid of an alkaline earth, I

intend to include the oxid.

I claim 1. A Waterproof casein glue containing casein, an alkaline earth hydroxid and animal glue in a condition readily soluble in 10 cold Water.

2. A waterproof casein glue containing casein, an alkaline earth hydroxid and from about 5% to 15% by Weight of animal glue in a condition readily soluble in cold water.

3. A waterproof casein glue containing 15 casein, calcium hydroxid and from 5% to 15% by weight of animal glue in a condition readily soluble in cold water.

In testimony whereof I have hereunto set my hand.

ANDREW A. DUNHAM. 

